Everyone is different but I am 54. I do the 3:1 cycling, strength w yoga and mental training. On top of it I add TRX aided back and chest work 4x/wk and added core 3x/week (usually the Beachbody series workouts). Key for me is NOT overdoing the training intensity, getting enough sleep, diet and recovery. I will dial it back to just some core and stretching if I feel like garbage. However I do feel like Wahoo SYSTM is pretty dialed in terms of stepping it up and backing off appropriately. Typically it’s self-inflicted consecutive long weekend rides or runs that put me over the top. 50s are young. Easier to get injured but no reason why you should not be able to feel like you are in your 30s! Now get out there and win one for the Gipper!! 
I’m enjoying this thread and appreciating how different we all are. “Fitness” is truly individual, as there are so many factors involved. After 20 years of losing my own fitness and getting fat, I used the free time created by the pandemic restrictions in 2020 to get serious about my health. One of the first things I did was hire a Wahoo coach to give me a clear foundation while I learned and adjusted to this new lifestyle. I have been consistently following a 2:1 SYSTM plan ever since.
At the start of this year, I started doing an Abi yoga session every day, plus strength and mobility sessions 3 days a week and riding 3-4 days. I rest on Sundays. I’m 59 and have put on almost 3 kg of lean muscle this year, while lowering my body fat 4%. In the last 14 months, my FTP has gone from 192 to 242. I say that not to brag, but to share that it IS possible to get really fit as an older athlete just by following the SYSTM programs. This morning, a friend I haven’t seen in months commented how buff I look. 
As others have shared, proper recovery is essential, essential, essential! So is proper nutrition. I attribute much of my lean muscle gain to the strength training and greatly increasing my protein intake. I’m currently at 1.92g/kg LBM. That’s probably high for most, but after some experimentation, it’s right for me. I now enjoy sustained energy throughout the day, no longer rely on caffeine and alcohol, and no longer binge eat.
In fact, my fitness gains have been so good that I committed last month to doing a half (70.3) Ironman next November 2023. When I first said yes, I thought I was out of my mind. I’ll be 60 then and haven’t competed in anything since I was in university. But I already see myself finishing strong. It will happen. The vision is very clear, and will be my guiding light as I spend the next 12 months learning to properly run and swim. I’ll be getting a Wahoo coach to guide me once again.
But before that happens, I will Storm the Castle in 3 weeks and tick the box on my 2022 goal of becoming a Knight of Sufferfest. It was a daunting goal when I made it in January and now seems like low hanging fruit thanks to all the training I’ve done this year. This fitness adventure has become so much fun. I’m addicted and so fortunate that my wife is fully supportive! My sincere thanks to the awesome team behind Sufferfest/Wahoo/SYSTM. 
All the best for your quest, but you will become a Knight of Sufferlandria. I am sure that will be just as rewarding. 
Good on you! Very inspiring - similar pandemic story and results.
Keep it up, and good luck on your KoS!
When I kicked off this topic, I wasn’t sure what responses I’d get and they are all great and make me realise that it’s about getting on with it, but listening to your body…
I am in no mood to slow down and plan to continue to enjoy as I always have… I completed Mallorca 312 last year and had loads of fun and really enjoyed it and have signed up for Haute Route Dolomites already for 2023…
Time to get down to it and enjoy it…
Thanks all…
Love the positivity of the Wahoo threads. Such a supportive community! Rock on!
Good on you. Great post!
Hi i am also signed up for Haute route dolomites 2023 are you using a training plan on wahoo? Trying to find a good one to peak for the event.
Six years ago i used trainer road 12 week plan for my first HR and it worked well. I haven’t seen a good training plan here but just resigned after a 6 year Zwift diversion
Try either the Mountain Fondo (under road events prep) it the 200ml Gravel plan if you’re concerned about volume not being high enough.
Basically, any will give you a really good base of you maintain the consistency